/* 全局重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Microsoft YaHei", sans-serif;
  }
  
  body {
    background: #f5f5f5;
  }
  
  /* 容器：左右分栏 */
  .container {
    display: flex;
    width: 100%;
    height: 100vh; /* 占满视口高度 */
  }
  
  /* 左侧时钟区域 */
  .clock-section {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: #e8f0f2;
  }
  
  /* 模拟时钟样式 */
  .analog-clock {
    width: 220px;
    height: 220px;
    border: 12px solid #333;
    border-radius: 50%;
    position: relative;
    margin-bottom: 30px;
    box-shadow: 0 0 20px rgba(0,0,0,0.2);
  }
  .clock-face {
    width: 100%;
    height: 100%;
    position: relative;
  }
  .hand {
    position: absolute;
    background: #333;
    transform-origin: bottom center; /* 指针旋转原点在底部 */
    left: 50%;
  }
  .hour-hand {
    width: 6px;
    height: 50px;
    top: 10%;
    margin-left: -3px;
  }
  .min-hand {
    width: 4px;
    height: 70px;
    top: 4%;
    margin-left: -2px;
  }
  .sec-hand {
    width: 2px;
    height: 80px;
    top: 2%;
    margin-left: -1px;
    background: #ff4444;
  }
  
  /* 数字时钟样式 */
  .digital-clock {
    text-align: center;
    font-size: 20px;
    color: #333;
  }
  #time {
    font-size: 36px;
    margin-bottom: 10px;
  }
  #date {
    font-size: 18px;
    opacity: 0.8;
  }
  
  /* 右侧计算器区域 */
  .calculator-section {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: #dcdcdc;
  }
  
  /* 计算器显示框 */
  #calc-display {
    width: 80%;
    max-width: 320px;
    height: 60px;
    font-size: 24px;
    text-align: right;
    padding: 0 15px;
    margin-bottom: 20px;
    border: none;
    border-radius: 8px;
    box-shadow: inset 0 0 5px rgba(0,0,0,0.1);
  }
  
  /* 按钮布局 */
  .calc-buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    width: 80%;
    max-width: 320px;
  }
  
  /* 按钮样式 */
  .btn {
    padding: 15px;
    font-size: 22px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    background: #fff;
    transition: all 0.2s;
  }
  .btn:hover {
    transform: scale(1.05);
  }
  .operator {
    background: #ff9800;
    color: #fff;
  }
  .equal {
    grid-column: span 2; /* 等号占两列 */
    background: #ff5722;
  }